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Porcine epidemic diarrhea virus (PEDV) is a highly contagious enteric pathogen of swine. Acute PEDV outbreaks have continually emerged in most swine-producing Asian countries and, recently, in the United States, causing significant economic losses in the pig industry. The spike (S) protein of PEDV is a type 1 transmembrane envelope glycoprotein and consists of the S1 and S2 domains, which are responsible for virus binding and fusion, respectively. Since the S1 domain is involved in a specific high-affinity interaction with the cellular receptor and induction of neutralizing antibody in the natural host, it is a primary target for the development of effective vaccines against PEDV. In this study, a codon-optimized PEDV S1 gene containing amino acid residues 25-738 was synthesized based on a multiple alignment of the S amino acid sequences of PEDV field isolates and used to establish a stable porcine cell line constitutively expressing the PEDV S1 protein. The purified recombinant S1 protein was found to mediate highly potent antibody responses in immunized rabbits. The antibodies strongly recognized the recombinant S1 protein from cell lysates and supernatants of S1-expressing cells, whereas they bound weakly to the authentic S protein of PEDV vaccine strain SM98-1. Furthermore, a serum neutralization test revealed that the rabbit antisera completely inhibit infection of the PEDV vaccine strain at a serum dilution of 1:16. We then tested the ability of vaccination with the recombinant S1 protein to protect piglets against PEDV. Late-term pregnant sows were inoculated intramuscularly with the purified S1 protein, and the outcome was investigated in passively immunized suckling piglets after a virulent PEDV challenge. The results showed that vaccination with S1 protein efficiently protected neonatal piglets against PEDV. Our data suggest that the recombinant S1 protein shows potential as an effective and safe subunit vaccine for PED prevention. [ABSTRACT FROM AUTHOR]

Migration of Ascaris lumbricoides into the gallbladder is rare, unlike ascariasis of the bile duct, and, when it does occur, treatment is generally by endoscopic or surgical extraction. We describe a case of the successful treatment of gallbladder ascariasis with conservative therapy. A 44-year-old Korean man was admitted because of nausea and right upper quadrant pain that did not respond to medical control and had worsened 1 day before admission. Abdominal ultrasonography showed a long, linear, moving echogenic structure in the distended lumen of the gallbladder, but no abnormal dilation of the bile duct. Computerized tomography showed a linear soft-tissue density in the dependent portion of the gallbladder. The patient presented with eosinophilia, and abnormal liver function results, but no fever or hepatomegaly. Based on these findings, and presuming a diagnosis of gallbladder ascariasis, we administered antiparasitic medication (albendazole 400 mg/day for 1 day). Seven days later, we obtained one adult female A. lumbricoides from the feces. The symptoms were fully resolved, and no moving structure could be visualized in the gallbladder by ultrasonography. We recommend that initial therapy for gallbladder ascariasis should involve conservative treatment, unless an associated disease is present or a complication arises. [ABSTRACT FROM AUTHOR]